418:
out-of-the-way places or in small or mobile laboratories. These and other considerations led to the search for a rapid method for the evaluation of the anti-knock quality of gasoline. Such substitute methods include FTIR, near infrared on-line analyzers, and others. Deriving an equation that can be used to calculate ratings accurately enough would also serve the same purpose, with added advantages. The term Octane Index is often used to refer to the use of an equation to determine a theoretical rating, in contradistinction to the direct measurements required for research or motor octane numbers. An octane index can be of great service in the blending of gasoline. Motor gasoline, as marketed, is usually a blend of several types of refinery grades that are derived from different processes such as straight-run gasoline, reformate, cracked gasoline etc. These different grades are blended in amounts that will meet final product specifications. Most refiners produce and market more than one grade of motor gasoline, differing principally in their anti-knock quality. Being able to make sufficiently accurate estimates of the octane rating that will result from blending different refinery products is essential, something for which the calculated octane index is specially suited.
2236:(English: "Additived Gasoline") - Petrobras stations brand it as "Petrobras Grid"; nevertheless, the octane rating is also 92 RON (these additives are used to improve the performance and efficiency of the engine, but they are not indicative of a higher octane rating). However, higher octane levels of gasoline are found in many stations (all stations in Brazil, regardless of the octane rating, have to conform the ANP requirement of 27% of ethanol mixed with the gasoline, and both "Common" and "Additived" gasolines can also be found in most of these stations), such as the "Premium Gasoline" (known in Portuguese as
2401:. From 1938 to 2018, Mexican government held a monopoly in the distribution of fuel, and its brands for unleaded fuel were "Pemex Magna" and "Pemex Premium", appearing in the early 1990s, before that, fuel was usually leaded. Mexican regulations do not enforce any particular labels to identify different grades of fuel as long as each grade is clearly labeled with distinct names and colors, but the long history of Pemex's colors has established a tradition of labeling regular fuel with green, premium fuel with red, and diesel with black. Gas station brands that use different colors include
2733:
2562:, which as the name suggests, has an octane rating of 102 RON. Although BP Ultimate Unleaded (with an octane rating of 97 RON) and BP Ultimate Diesel are both widely available throughout the UK, BP Ultimate Unleaded 102 was available throughout the UK in only 10 filling stations, and was priced at about two and half times more than their 97 RON fuel. In March 2010, BP stopped sales of Ultimate Unleaded 102, citing the closure of their specialty fuels manufacturing facility. Shell V-Power is also available, but in a 99 RON octane rating, and
2087:
evaporate away and leave behind fewer deposits such as "varnish" (gasoline components, particularly alkenes and oxygenates slowly polymerize into solids). Aircraft also typically have dual "redundant" ignition systems which are nearly impossible to tune and time to produce identical ignition timing, so using a lighter fuel that's less prone to autoignition is a wise "insurance policy". For the same reasons, those lighter fuels which are better solvents are much less likely to cause any "varnish" or other fouling on the "backup" spark plugs.
2038:
spark requires more energy from the ignition system, which in turn increases the parasitic electrical load on the engine. The spark also must begin earlier in order to generate sufficient heat at the proper time for precise ignition. As octane, ignition spark energy, and the need for precise timing increase, the engine becomes more difficult to "tune" and keep "in tune". The resulting sub-optimal spark energy and timing can cause major engine problems, from a simple "miss" to uncontrolled detonation and catastrophic engine failure.
2079:". They run best on lower-octane, slower-burning fuels that require less heat and a lower compression ratio for optimum vaporization and uniform fuel-air mixing, with the ignition spark coming as late as possible in order to extend the production of cylinder pressure and torque as far down the power stroke as possible. The main reason for using high-octane fuel in air-cooled engines is that it is more easily vaporized in a cold carburetor and engine and absorbs less intake air heat which greatly reduces the tendency for
306:
2232:- since 2011). Along with the "Common" gasoline, there is a second type of gasoline that can also be found in most stations in Brazil. This gasoline is also mixed with 27% of ethanol (to comply with the ANP regulation, that prohibits the sale of the 100% "pure gasoline" compound in all Brazilian stations), but a few detergent and dispersant additives are also included in the compound. This type of gasoline is known in Portuguese as
2114:, and possible increased range before refueling, some general aviation pilots attempt to save money by tuning their fuel-air mixtures and ignition timing to run "lean of peak". Additionally, the decreased air density at higher altitudes (such as Colorado) and temperatures (as in summer) requires leaning (reduction in amount of fuel per volume or mass of air) for the peak EGT and power (crucial for takeoff).
409:), is derived from testing the gasoline in ordinary multi-cylinder engines (rather than in a purpose-built test engine), normally at wide open throttle. This type of test was developed in the 1920s and is still reliable today. The original RdON tests were done in cars on the road, but as technology developed the testing was moved to chassis dynamometers with environmental controls to improve consistency.
2740:"Octane" is colloquially used in the expression "high-octane". The term is used to describe a powerful action because of the association with the concept of "octane rating". This is a misleading term, because the octane rating of gasoline is not directly related to the power output of an engine. Using gasoline of a higher octane than an engine is designed for cannot increase its power output.
2128:
1970:
455:
2631:
557:
204:
2313:, Aral Ultimate) at almost every fuel station. "Normal" 91 RON is only rarely offered because lower production amounts make it more expensive than "Super" 95 RON. Due to a new European Union law, gas stations are being required to offer a minimum rate of the new mixture of "Super" 95 RON with up to 10% ethanol branded as "Super E10".
244:
octane rating of 90. A rating of 90 does not mean that the gasoline contains just iso-octane and heptane in these proportions, but that it has the same detonation resistance properties (generally, gasoline sold for common use never consists solely of iso-octane and heptane; it is a mixture of many hydrocarbons and often other additives).
2511:
95 RON is available as 'Premium Petrol'. As of 2022, LIOC fillings stations offer a new fuel labelled as 'XtraPremium' Petrol which is marketed as 'Euro 3' standard petrol. Similarly 95 RON petrol is offered as 'XtraPremium' 95 Petrol. Sri Lanka adopted RON 100 Octane 100 from July 2024. It is the 8th country in the world to use RON 100.
165:, but when one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front. The fuel-air charge is meant to be ignited by the spark plug only, and at a precise point in the piston's stroke. Knock occurs when the peak of the combustion process no longer occurs at the optimum moment for the
2326:
poWer 99 with an RON value of 99 which was initially available only in
Bangalore, Pune and now in Mumbai but was expected to roll out in other major cities soon. India's economy-class vehicles usually have compression ratios under 10:1, thus enabling them to use lower-octane petrol without engine knocking.
2670:
have an octane rating of 100 and 0, respectively. Because of its more volatile nature, n-heptane ignites and knocks readily, which gives it a relatively low octane rating; the isomer iso-octane causes less knocking because it is more branched and combusts more smoothly. In general, branched compounds
2451:
Blaze and is rated at 100 RON. Other
Premium Plus grades like Seaoil Extreme 97, Shell V-Power Racing and Unioil Gas 97 are rated at 97 RON, while Phoenix Premium 98 is rated at 98 RON. Premium grades such as Caltex Gold, Petron XCS, Phoenix Premium 95, Seaoil Extreme 95, Shell V-Power Nitro+, Unioil
2274:
Denmark: 95 RON is a common budget choice, with 95 and 98 being widely available, and 92 rarely seen as it has been phased out during the 2010s. A selection of brands offers >=100 options, under trademarked names. However several fuel stations are phasing out 92 RON. By law, it is decided that all
2207:
Brazil: As defined by federal law, the RON standard is used and all types of gasoline sold in all gas stations throughout the country are unleaded (the latter since 1991). By default, it was defined by the federal government that the regular (and the lowest) octane standard in Brazil is 92 RON, known
2200:
Bangladesh: Two types of fuel are available at petrol stations in
Bangladesh. Motor Gasoline Regular (marketed as "Petrol") which has RON 80 rating, and Motor Gasoline Premium (marketed as "Octane") which has RON 95 rating. Petrol stations in Bangladesh are privatised, but the prices are regulated by
2620:
Zimbabwe: 93 octane available with no other grades of fuels available, E10 which is an ethanol blend of fuel at 10% ethanol is available the octane rating however is still to be tested and confirmed but it is assumed that it is around 95 Octane. E85 available from 3 outlets with an octane rating AKI
2478:
1.44 (US$ 0.38) and SR 2.10 (US$ 0.56) (as of 14 April 2019) per litre respectively; and is currently being increased at a quarterly rate to bring it up to the worldwide average by 2020. Prior to 2006, only Super
Premium RON 95 was available and the pumps were not systematically coloured. The public
2431:
New
Zealand: 91 RON "Regular" and 95 RON "Premium" are both widely available. 98 RON is available instead of 95 RON at some (BP, Mobil, Gull) service stations in larger urban areas (newer BP stations also offer 95 by blending 91 and 98 where 98 is available). 100 RON is available
2342:
stations only sell RON 92 and 95 gasoline. Shell launched a new variant, "Regular", rated at 90 RON, in early 2018, but this was discontinued in
January 2022. However, after 6 years of discontinuation of Pertamax Plus, In July 2023 Pertamina launched the Pertamax Green 95 which made of sugarcane and
2573:
United States: in the US octane rating is displayed in AKI. In most areas, the standard grades are 87, 89–90, and 91–94 AKI. In the Rocky
Mountain (high elevation) states, 85 AKI (90 RON) is the minimum octane, and 91 AKI (95 RON) is the maximum octane available in fuel. The reason for this is that
2532:
Ukraine: 80 RON and 98 RON gasoline is available. The standard gasoline is 95 RON, but 92 RON gasoline is also widely available and popular for older cars. There is no government regulation for gasoline with RON higher than 98 so some stations are marketing 100 RON gasoline when in reality this can
2510:
Sri Lanka: Sri Lanka switched their regular gasoline from 90 RON to 92 RON on
January 1, 2014. In Ceypetco filling stations, 92 RON is the regular automotive fuel and 95 RON is called 'Super Petrol', which comes at a premium price. In LIOC filling stations, 92 RON is the regular automotive fuel and
2289:
Finland: 95 and 98 (RON), advertised as such, at almost all gas stations. Most cars run on 95, but 98 is available for vehicles that need higher octane fuel, or older models containing parts easily damaged by high ethanol content. Shell offers V-Power, advertised as "over 99 octane", instead of 98.
2037:
Because octane is a measured and/or calculated rating of the fuel's ability to resist autoignition, the higher the octane of the fuel, the harder that fuel is to ignite and the more heat is required to ignite it. The result is that a hotter ignition spark is required for ignition. Creating a hotter
243:
that would have the same anti-knocking capability as the fuel under test. The percentage, by volume, of 2,2,4-trimethylpentane in that mixture is the octane number of the fuel. For example, gasoline with the same knocking characteristics as a mixture of 90% iso-octane and 10% heptane would have an
2578:
draws in less air mass per cycle because of the reduced density of the atmosphere. This directly translates to less fuel and reduced absolute compression in the cylinder, therefore deterring knock. It is safe to fill a carbureted car that normally takes 87 AKI fuel at sea level with 85 AKI fuel in
2446:
Philippines: All automotive fuels are unleaded since
December 23, 2000. Since late 2013, three grades of gasoline are available: Premium Plus, Premium (mid-grade) and Regular. Law requires the Premium Plus grade to be 97 RON or higher; Premium at 95 RON; Regular at 91 RON. Premium Plus grade fuels
2325:
India: India's ordinary and premium petrol options are of 91 RON. The premium petrols are generally ordinary fuels with additives, that do not really change the octane value. Two variants, "Speed 93" and "Speed 97", were launched, with RON values of 93 and 97. In 2017, Hindustan
Petroleum launched
2282:
Egypt: Egyptian fuel stations had 90 RON until July 2014 when the government found no remaining use for it, leaving only 92 RON and 95 RON. 80 RON is found in a very limited number of fuel stations as they are used only for extremely old cars that cannot cope with high octane fuel. 95 RON was used
2193:
used to sell 100 RON unleaded fuel (10% ethanol content) at a small number of its service stations (originally only two, but then expanded to 67 outlets nationwide) (stopped in September 2014). All fuel in Australia is unleaded except for some aviation fuels. E85 unleaded fuel is also available at
429:
used in piston aircraft engines common in general aviation have a slightly different method of measuring the octane of the fuel. Similar to an AKI, it has two different ratings, although it is usually referred to only by the lower of the two. One is referred to as the "aviation lean" rating, which
389:
Because of the 8 to 12 octane number difference between RON and MON noted above, the AKI shown in Canada and the United States is 4 to 6 octane numbers lower than elsewhere in the world for the same fuel. This difference between RON and MON is known as the fuel's sensitivity, and is not typically
2612:
Venezuela: 91 RON and 95 RON gasoline is available nationwide, in all PDV gas stations. 95 RON gasoline is the most widely used in the country, although most cars in Venezuela would work with 91 RON gasoline. This is because gasoline prices are heavily subsidized by the government (US$ 0.0083 per
2427:
Netherlands: 95 RON "Euro" is sold at every station, whereas 98 RON "Super Plus" is being phased out in favor of "premium" fuels, which are all 95 RON fuels with extra additives. Shell V-Power is a 97 RON (labelled as 95 due to the legalities of only using 95 or 98 labelling), some
2638:
Due to its name, the chemical "octane" is often misunderstood as the only substance that determines the Octane rating (or octane number) of a fuel. This is an inaccurate description. In reality, the octane rating is defined as a number describing the stability and ability of a fuel to prevent an
2616:
Vietnam: 92 RON is in every gas station and 95 RON is in the urban area. They start selling A92-E5 gasoline (92 RON with 5 percent of ethanol) at 2017. On January 1, 2018, Vietnamese government forced every gas station stop selling 92 RON and sell 95 RON + A92-E5 instead. From 2022, Vietnam will
2034:: the amount of applied energy required to initiate combustion. Since higher octane fuels have higher activation energy requirements, it is less likely that a given compression will cause uncontrolled ignition, otherwise known as autoignition, selfignition, pre-ignition, detonation, or knocking.
2329:
Indonesia: Indonesia's "Premium" gasoline, rated at 88 RON, was the lowest grade gasoline, but was phased out by 2021. Other options have been "Pertalite", rated at 90 RON; "Pertamax", rated at 92 RON; "Pertamax Plus", rated at 95 RON (now replaced by Pertamax Green in July 2023); and "Pertamax
2747:
companies boasted of "high octane" levels in their gasoline advertisements. The compound adjective "high-octane", meaning powerful or dynamic, is recorded in a figurative sense from 1944. By the 1990s, the phrase was commonly being used as a word intensifier, and it has found a place in modern
2346:
Iran: 'regular' gasoline has an octane rating of 87 RON, which is the most prevalent type of gasoline available throughout the country. Select gas stations within major cities also offer 'Super' 95 RON. Due to high air pollution, an environmentally cleaner variety, marketed as Euro-4, is being
61:. The higher the octane number, the more compression the fuel can withstand before detonating. Octane rating does not relate directly to the power output or the energy content of the fuel per unit mass or volume, but simply indicates the resistance to detonating under pressure without a spark.
2086:
With their reduced densities and weight per volume of fuel, the other obvious benefit is that an aircraft with any given volume of fuel in the tanks is automatically lighter. And since many airplanes are flown only occasionally and may sit unused for weeks or months, the lighter fuels tend to
2435:
Norway: 95 RON are widely available, but 98 RON is also available at Shell, here it goes under the name v-power; it is 10-20% more expensive as 95 RON fuel. In 2023 95 RON fuel got change to 95E10 and 98 RON to 98E5. SHELL still has 98 octane under the name v-power, but also most of the Esso
417:
The evaluation of the octane number by either of the two laboratory methods requires a special engine built to match the tests' rigid standards, and the procedure can be both expensive and time-consuming. The standard engine required for the test may not always be available, especially in
2423:
Myanmar: Most petrol stations carry 92 RON as standard especially in rural areas. Most larger cities and highway stations have introduced 95 RON in the past few years. The highest grade available is 97 RON which is only sold by a few stations in Yangon and Nay Pyi Taw (e.g., PTT, MMTM,
2188:
fuel is 91 RON, "premium" unleaded with 95 RON is widely available, and 98 RON fuel is also very common. Shell used to sell 100 RON fuel (5% ethanol content) from a small number of service stations, most of which are located in major cities (stopped in August 2008).
2360:
Israel: 95 RON & 98 RON are normally available at most automotive fuel stations. 96 RON is no longer available as of 2010. 95 RON is preferred because it is cheaper and performance differences are not significant. "Regular" fuel is 95 RON. All variants are
334:
under controlled conditions, and comparing the results with those for mixtures of iso-octane and n-heptane. The compression ratio is varied during the test to challenge the fuel's antiknocking tendency, as an increase in the compression ratio will increase the chances of knocking.
2455:
Poland: Eurosuper 95 (RON 95) is sold in every gas station. Super Plus 98 (RON 98) is available in most stations, sometimes under brand (Orlen - Verva, BP - Ultimate, Shell - V-Power) and usually containing additives. Shell offers V-Power Racing fuel which is rated RON
364:
In most countries in Europe, and in Australia and New Zealand, the "headline" octane rating prominently displayed on the pump is the RON, but in Canada, the United States, and Mexico, the headline number is the simple mean or average of the RON and the MON, called the
4265:
430:
for ratings up to 100 is the same as the MON of the fuel. The second is the "aviation rich" rating and corresponds to the octane rating of a test engine under forced induction operation common in high-performance and military piston aircraft. This utilizes a
2357:, "green"), only a few fuel stations (Agip, IP, IES, OMV) offer 98 RON as the premium type, many Shell and Tamoil stations close to the cities offer also V-Power Gasoline rated at 100 RON. Recently Agip introduced "Blu Super+", a 100 RON gasoline.
2587:
in nearly all modern automobiles produced from the late 1980s and early 1990s onwards. 85 AKI fuel is not recommended for modern automobiles and may cause damage to the engine and decreased performance. Another disadvantage to this strategy is that most
2723:
measurement). The large differences between the octane ratings for the isomers show that the compound octane itself is clearly not the only factor that determines octane ratings, especially for commercial fuels consist of a wide variety of compounds.
2528:
Turkey: 95 RON and 95+ RON widely available in gas stations. 91 RON (Regular) has been dropped in 2006. 98 and 100 RON (Shell V-Power Racing) has been dropped in late 2009. The Gas which has been advertised 97 RON has been dropped in 2014 and renamed
2110:" (more fuel than can be burned with the available air) or "lean of peak" (less fuel, leaving some oxygen in the exhaust) as either will keep the fuel-air mixture from detonating prematurely. Because of the high cost of unleaded, high-octane
2442:
Pakistan: 3 types of fuel available. 92, HOBC 95 & HOBC 97 RON. Super marketed as 92 RON, 95 RON marketed by Shell as V-Power and 97 RON by Total Parco Pakistan & Pakistan State Oil (PSO). HOBC pricing was deregulated in October,
2260:
Colombia: "Ecopetrol", Colombia's monopoly of refining and distribution of gasoline establishes a minimum AKI of 81 octanes for "Corriente" gasoline and minimum AKI of 87 octanes for "Extra" gasoline. (91.5 RON corriente, and 95 RON for
355:
to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern pump gasoline will be about 8 to 12 lower than the RON, but there is no direct link between RON and MON. See the table below.
2321:
Hong Kong: only 98 RON is available in the market. There have been calls to re-introduce 95 RON, but the calls have been rejected by all automotive fuel station chains, citing that 95 RON was phased out because of market
79:
because diesel engines (also called compression-ignition engines) do not compress the fuel, but rather compress only air, and then inject fuel into the air that was heated by compression. Gasoline engines rely on ignition of compressed
2592:
vehicles are unable to produce full power, even when using the "premium" 91 AKI fuel. In some east coast states, up to 94 AKI (99 or 100 RON) is available. As of January 2011, over 40 states and a total of over 2500 stations offer
2452:
Gas 95 and Total Excellium are rated at 95 RON. Regular grades such as Caltex Silver, Petron Xtra Unleaded, Phoenix Super Regular 91, Seaoil Extreme U+, Shell FuelSave Unleaded, Unioil Gas 91 and Total Premier are rated at 91 RON.
2466:
countries: 92 RON is the minimum available, the standard is 95 RON is sold in every gas station. 98 RON is available in most stations. As a "premium" fuel, 100 RON is sold, Gazpromneft and Lukoil both variants are
2278:
Ecuador: "Extra" and Ecopais (5% etanol) with 85 RON, "Eco Plus" with 89 RON and "Super Premium" with 95 (RON). Extra/Ecopais and Super Premium are available in all fuel stations. "Extra" is the most commonly used. All fuels are
2075:. Higher compression ratios necessarily add parasitic load to the engine, and are only necessary if the engine is being specifically designed to run on high-octane fuel. Aircraft engines run at relatively low speeds and are "
2416:
Mongolia: 92 RON and 95 RON (advertised as A92 and A95 respectively) are available at nearly all stations while slightly fewer stations offer 80 RON (advertised as A80). 98 RON (advertised as A98) is available in select few
92:. Therefore, being able to compress the air/fuel mixture without causing detonation is important mainly for gasoline engines. Using gasoline with lower octane than an engine is built for may cause engine knocking and/or
4217:
4462:
2364:
Japan: Since 1986, "regular" is >=89 RON, and "high octane" is >=96 RON, lead free. Those values are defined in standard JIS K 2202. Sometimes "high octane" is sold under different names, such as
351:), is determined at 900 rpm engine speed instead of the 600 rpm for RON. MON testing uses a similar test engine to that used in RON testing, but with a preheated fuel mixture, higher engine speed, and variable
2874:
The new fuel was called BAM 100, or 100/130 octane, the latter designation because it gave the British aircraft up to 30 percent more horsepower when taking off and climbing than ordinary 100 octane would have
2267:
Croatia: All fuel stations offer unleaded "Eurosuper BS" (abbreviation "BS" meaning "no sulfur content") 95 RON fuel, many also offer "Eurosuper Plus BS" 98 RON. Some companies offer 100 RON fuel instead of
68:, which may yield higher power for these engines. The added power in such cases comes from the way the engine is designed to compress the air/fuel mixture, and not directly from the rating of the gasoline.
2377:
Malaysia: 95 RON, 97 RON and 100 RON. "Regular" unleaded fuel is 95 RON; "Premium" fuel is rated at 97 RON (Shell's V-Power Racing is rated minimum 97 RON). Petron sells 100 RON in selected
2106:, in the worst case destroying the engine within seconds. Pilots are taught in primary training to avoid settings that produce the highest exhaust gas temperatures, and run the engine either "rich of peak
2479:
did not know what octane rating was, so education campaigns were started, advising people to use "red petrol" only for high end cars, and to save money by using "green petrol" for regular cars and trucks.
2283:
limitedly due to its high price (more than twice the price of 92 RON). But after the increasing the prices again in 2018, 95 RON price became only 15% higher than 92 RON, so it started to gain popularity.
2221:
2290:
In the beginning of 2011 95 RON was replaced by 95E10 containing 10% ethanol, and 98 RON by 98E5, containing 5% ethanol. ST1 also offers RE85 on some stations, which is 85% ethanol made from
2522:
Thailand: 95 RON E0, 95 RON E10, 91 RON E10, 95 RON E20 are widely available in all parts of Thailand. 97 RON E10 fuel is also available in some Bangchak's filling stations in many parts of Thailand.
2254:
China: 92 and 95 (RON) (previously 93 and 97) are commonly offered. In limited areas higher rating such as 98 RON is available. In some rural areas it can be difficult to find fuel with over 92 RON.
64:
Whether or not a higher octane fuel improves or impairs an engine's performance depends on the design of the engine. In broad terms, fuels with a higher octane rating are used in higher-compression
169:. The shock wave creates the characteristic metallic "pinging" sound, and cylinder pressure increases dramatically. Effects of engine knocking range from inconsequential to completely destructive.
2220:(English: "Regular Gasoline"). This type of gasoline can be found in most Brazilian petrol stations and does not have any additives, except the inclusion of 27% of ethanol (as required by the
2098:
control. Leaning — reducing the mixture from its maximum amount — must be done with knowledge, as some combinations of fuel mixture and throttle position (that produce the highest ) can cause
4192:
2474:
are used to make the colour of the fuel match that of the pump. While petrol stations in Saudi Arabia are privatised, the prices are regulated by the authorities and have a fixed at
2470:
Saudi Arabia: Two types of fuel are available at all petrol stations in Saudi Arabia. "Premium 91" (RON 91) has green pumps, and "Super Premium 95" (RON 95) where the pumps are red.
2501:
South Africa: "regular" unleaded fuel is 95 RON in coastal areas. Inland (higher elevation) "regular" unleaded fuel is 93 RON; once again most fuel stations optionally offer 95 RON.
2507:
Spain: 95 RON "Euro" is sold in every station with 98 RON "Super" being offered in most stations. Many stations around cities and highways offer other high-octane "premium" brands.
107:. The octane rating affected not only the performance of the gasoline, but also its versatility; the higher octane fuel allowed a wider range of lean to rich operating conditions.
258:
Where the octane number is raised by blending in ethanol, energy content per volume is reduced. Ethanol energy density can be compared with gasoline in heat-of-combustion tables.
2428:
independent tests have shown that one year after introduction it was downgraded to 95 RON, whereas in neighboring Germany Shell V-Power consists of the regular 100 RON fuel.
2381:
Mexico: The standard octane index is 87 AKI for regular fuel and anywhere from 91 to 93 AKI for premium fuel, although 91 AKI is the most common octane number for premium fuel.
2194:
several United service stations across the country. By 2018, E10 fuel had become quite common, and is available at almost every major fuel station, except in Western Australia.
3560:
4053:
224:
are a family of hydrocarbons that are typical components of gasoline. They are colorless liquids that boil around 125 °C (260 °F). One member of the octane family,
2197:
Bahrain: 91 and 95 (RON), standard in all gasoline stations in the country and advertised as (Jayyid) for Regular or 91 and (Mumtaz) for Premium or 95 and 98 (RON) as super.
297:
was once a common additive, but concerns about its toxicity have led to its use for fuels for road vehicles being progressively phased out worldwide beginning in the 1970s.
261:
It is possible for a fuel to have a Research Octane Number (RON) more than 100, because iso-octane is not the most knock-resistant substance available today. Racing fuels,
4866:
2068:
and the compounds in the fuel that have the most detrimental effects on the engine fuel system components, as such acids corrode many metals used in gasoline fuel systems.
3389:
2634:
Gas stations have gasoline with different octane ratings. Higher numbers indicate that the fuel can better avoid unintended combustions within the cylinders of the engine.
4473:
2819:
4725:
2917:
2698:
So, octane does not enhance the explosion in the cylinder like most people think... It just prevents the air-fuel mixture from igniting before the spark plug does it.
2385:
is the only station offering 93 AKI fuel in Mexico, at a premium of 5% to 10% over standard 91 AKI fuel. Valero stations are usually present in main cities, such as
2690:
This statement is inaccurate, even though the alternatives indeed have a high octane rating. Alternative fuels do not contain octane, and cannot "provide" octane.
2701:
While the first part of this statement is factual, the complete statement implies that octane is the only chemical contributing to octane rating, which is false.
3535:
2374:
Lithuania: 95 RON and 98 RON are widely available. In some gas stations E85 (bioethanol) gasoline, 98E15 (15% of ethanol), 98E25 (25% of ethanol) are available.
2064:. They also evaporate away much more easily than heavier, lower-octane fuel which leads to more accumulated contaminants in the fuel system. It is typically the
3321:
3275:
4881:
3594:
607:
and iso-octane are exactly 0 and 100, respectively, by the definition of octane rating. The following table lists octane ratings for various other fuels.
2247:
Canada: in Canada octane rating is displayed in AKI. In most areas, the standard grades are 87 (regular), 89 (mid-grade) and 91–94 (premium) AKI. In the
4028:
4013:
4089:
2671:
with a higher intermolecular force (e.g. London dispersion force for iso-octane) will have a higher octane rating, because they are harder to ignite.
2071:
During the compression stroke of an internal combustion engine, the temperature of the air-fuel mix rises as it is compressed, in accordance with the
4251:
3834:
3129:
2943:
3873:
2275:
gasoline companies from July 2010 to January 2020 should use a mix containing 5% bioethanol in the gasoline and increased to 10% after January 2020.
239:
The octane rating of gasoline is measured in a test engine and is defined by comparison with the mixture of 2,2,4-trimethylpentane (iso-octane) and
4535:
2601:
fuel with 94–96 AKI. Often, filling stations near US racing tracks will offer higher octane levels such as 100 AKI from separate dedicated pumps.
2264:
Costa Rica: RECOPE, Costa Rica's distribution monopoly, establishes the following ratings: Plus 91 (at least 91 RON) and Super (at least 95 RON).
3436:
Daniel, Ritchie (2012). "Combustion performance of 2,5-dimethylfuran blends using dual-injection compared to direct-injection in an SI engine".
3094:
3928:
3775:
Verhelst, Sebastian; Sierens, Roger; Verstraeten, Stefaan (2006). "A Critical Review of Experimental Research on Hydrogen Fueled SI Engines".
4845:
3712:
2977:
2798:
2687:
When faced with the removal of lead as the primary octane provider in gasoline, refiners had two available alternatives, BTEX and ethanol....
2350:
Ireland: 95 RON "unleaded" is the only gasoline type available through stations, although E5 (99 RON) is becoming more commonplace.
4490:
2439:
Oman: 91 RON, 95 RON and 98 RON. "Regular" unleaded fuel is 91 RON; "Premium" fuel is rated at 95 RON; 98 RON in selected outlets.
2053:, so the practice of running an engine "rich" to use excess fuel to aid in cooling requires richer and richer mixtures as octane increases.
4196:
2679:
There are numerous articles circulating the internet that propagate this misunderstanding. Below are some factually inaccurate statements.
3363:
4516:
2347:
introduced in metropolitan areas instead of the Regular, which boasts an octane rating of 91 RON and sulphur levels not exceeding 50 ppm.
4392:
2856:
3663:
Eyidogan, Muharrem (2010). "Impact of alcohol–gasoline fuel blends on the performance and combustion characteristics of an SI engine".
3898:
2836:
2463:
571:
567:
3479:
2927:
2900:
2301:
Germany: "Super E5 and E10" 95 RON and "Super Plus E5" 98 RON are available practically everywhere. Big suppliers such as
2201:
the authorities and have a fixed price at BDT 86.00 (US$ 1.04) and BDT 89.00 (US$ 1.07) (as of 1 March 2018) per litre respectively.
2167:
2017:
538:
255:). They are only a measure of the fuel's tendency to burn in a controlled manner, rather than exploding in an uncontrolled manner.
4046:
3070:
3567:
2504:
South Korea: "regular" unleaded fuel is 91~94 RON, "premium" is 95+ RON nationally. However, not all gas stations carry "premium."
4749:
3848:
3026:
2605:
3386:
3190:
4332:
2041:
The other rarely-discussed reality with high-octane fuels associated with "high performance" is that as octane increases, the
2149:
2145:
1995:
1991:
476:
472:
2732:
519:
3736:
4440:
4308:
899:
491:
4924:
3406:
3313:
3267:
4283:
2316:
Greece (Hellas): 95 RON (standard unleaded), 98 & 100 RON unleaded offered by some companies (e.g. EKO, Shell, BP).
4156:
3214:
3004:
2491:
3539:
1980:
498:
3761:
4878:
4120:
3598:
2575:
331:
130:
54:
4677:
2817:
Dabelstein, Werner; Reglitzky, Arno; Schütze, Andrea; Reders, Klaus; Brunner, Andreas (2016). "Automotive Fuels".
2536:
United Kingdom: 'regular' gasoline has an octane rating of 95 RON, with 97 RON fuel being widely available as the
2498:
have 3 grades of gasoline. Typically, these are 92, 95, and 98 RON. However, since 2009, Shell has removed 92 RON.
2138:
1999:
1984:
583:
465:
3040:
Al-Haj Ibrahim, H.; Al-Kassmi, M. (October 2000). "Determination of calculated octane index for motor gasoline".
2420:
Montenegro: 95 RON is sold as a "regular" fuel. As a "premium" fuel, 98 RON is sold. Both variants are unleaded.
2045:
and energy content of the fuel per unit of weight are reduced. The net result is that to make a given amount of
4914:
505:
180:
2617:
start selling gasoline according to Euro 5 standards, with the choices 95 RON and 97 RON(in SFC gas stations).
2257:
Chile: 93, 95 and 97 RON are standard at almost all gas stations thorough Chile. The three types are unleaded.
2204:
Botswana: 93 and 95 RON are standard at almost all gas stations thorough Botswana. The two types are unleaded.
1168:"EuroSuper" or "EuroPremium" or "Regular unleaded" in UK/Europe, "SP95" and "SP95-E10" (10% ethanol blend) in
2447:
are exempted from having an ethanol blend, although the only Premium Plus grade available without ethanol is
4005:
2107:
1768:
278:
233:
191:
that monitors if knock is being produced by the fuel being used. In modern computer-controlled engines, the
4241:
4078:
3631:
2662:
of a fuel with respect to this isomer of octane, thus the name "octane rating". By definition, the isomers
2643:(i.e. delocalized explosions from the spark plug). This phenomenon of combustion is more commonly known as
4557:
3500:
3133:
2715:
2651:
2459:
Portugal: 95 RON "Euro" is sold in every station and 98 RON "Super" being offered in almost every station.
2286:
Estonia: 95 RON and 98 RON are widely available. E85 (bioethanol) gasoline found in very few gas stations.
1706:
1462:
487:
305:
225:
207:
195:
will be automatically altered by the engine management system to reduce the knock to an acceptable level.
4346:
3877:
4919:
4652:
1833:
4543:
3338:
3292:
2432:
at selected NPD service stations in the South Island and in very limited locations in the North Island.
2947:
1325:"Shell V-Power 98", "Caltex Platinum 98 with Techron", "Esso Mobil Synergy 8000" and "SPC LEVO 98" in
4615:
3808:
3672:
3445:
3105:
4828:
McAllister, Sara; Chen, Jyh-Yuan; Fernandez-Pello, A. Carlos (2011). "Premixed Piston IC Engines".
4726:"Why do highly branched alkanes have higher octane numbers than their corresponding linear isomer?"
4142:
2291:
2057:
1582:
2343:
a mixture of Pertamax 92 and the price is slightly cheaper than Pertamax Turbo which rated 98 RON.
2180:
The selection of octane ratings available at filling stations can vary greatly between countries.
2091:
2049:, more high-octane fuel must be burned in the engine. Lighter and "thinner" fuel also has a lower
81:
4773:
Balaban, A. T. (1983). "Topological indices based on topological distances in molecular graphs".
4494:
3784:
3632:"Structure-property analysis of octane numbers for hydrocarbons (alkanes, cycloalkanes, alkenes)"
3154:
Balaban, A. T. (1983). "Topological indices based on topological distances in molecular graphs".
2448:
2241:
1058:
1044:
252:
2647:
or self-ignition, which causes damage to pistons over time and reduces the lifespan of engines.
2094:
is directly controlled by the pilot, via a knob and cable or lever similar to (and next to) the
3356:
4899:
4841:
4631:
3708:
3246:
2973:
2923:
2896:
2832:
2794:
2640:
2031:
1528:
807:
426:
274:
166:
100:
50:
4384:
3702:
4833:
4782:
4623:
3816:
3680:
3453:
3163:
2824:
2786:
2190:
2080:
2042:
1816:
3906:
2781:
Stauffer, Eric; Dolan, Julia A.; Newman, Reta (2008). "Flammable and Combustible Liquids".
512:
4929:
4885:
4701:
3393:
2644:
2248:
2099:
2046:
694:
352:
192:
121:
85:
58:
4800:
3471:
4619:
3812:
3676:
3449:
3059:
2639:
engine from unwanted combustions that occur spontaneously in the other regions within a
2621:
index of between 102 and 105 depending on the base gasoline the ethanol is blended with.
2271:
Cyprus: All fuel stations offer unleaded 95 and 98 RON, and a few offer 100 RON as well.
2861:
2613:
gallon 95 RON, vs US$ 0.0061 per gallon 91 RON). All gasoline in Venezuela is unleaded.
2580:
1586:
1359:
810:
759:
743:
294:
240:
184:
176:—they are two separate events with pre-ignition occurring before the combustion event.
158:
127:
3852:
3018:
4908:
4890:
2889:
2790:
2762:
2382:
2335:
2334:
began selling "Pertamax Turbo", rated at 98 RON, as a replacement for Pertamax Plus.
2310:
2072:
2050:
434:, and uses a significantly richer fuel/air ratio for improved detonation resistance.
76:
72:
65:
2060:
compounds incompatible with the stock fuel system components, which also makes them
4448:
3457:
2589:
2103:
1800:
1544:
431:
266:
188:
173:
161:
in the cylinder does not result from propagation of the flame front ignited by the
104:
93:
17:
4582:
3245:. Society of Automotive Engineers international congress and exposition. Detroit.
2828:
2394:
2251:, gasoline is often available without any blend of ethanol, but only up to 91 AKI.
103:
was extremely important in determining aero engine performance in the aircraft of
4837:
4627:
2519:
Taiwan: 92 RON, 95 RON and 98 RON are widely available at gas stations in Taiwan.
441:, has an aviation lean rating of 100 octane, and an aviation rich rating of 130.
273:
may have octane ratings of 110 or significantly higher. Typical "octane booster"
210:(iso-octane) (upper) by definition is assigned the octane rating of 100, whereas
4421:
Department of Energy Department Circular No. DC2013-09-0021, September 19, 2013.
4360:
4309:"Hindustan Petroleum Launches High Performance 99 Octane Fuel - NDTV CarAndBike"
2584:
2475:
2390:
2127:
2076:
2061:
1969:
1863:
1480:
1409:
1330:
1104:
987:
680:
454:
46:
4895:
4164:
3820:
3728:
3684:
3241:
Henig, Y.; Addagaria, S.; Miller, D. L.; Wilk, R. D.; Cernansky, N. P. (1989).
4246:
3505:
2630:
2525:
Trinidad and Tobago: 92 RON (Super) and 95 RON (Premium) are widely available.
2487:
1879:
1603:
967:
933:
878:
861:
627:
390:
published for those countries that use the Anti-Knock Index labelling system.
162:
89:
4195:(in Spanish). Ecuador: Instituto Ecuatoriano de Normalizacion. Archived from
4178:
3796:
4786:
4653:"A Brief History of Octane in Gasoline: From Lead to Ethanol | White Papers"
4287:
3976:
3167:
2567:
2545:
2495:
2471:
2402:
2386:
2339:
2331:
2302:
2295:
2213:
1687:
1654:
1405:
1376:
1342:
1326:
1258:
1242:
1189:"Premium" or "Super unleaded" gasoline in US and Canada (10% ethanol blend)
1150:
1146:
1142:
1108:
1087:
1029:
1025:
1008:
1004:
983:
914:
845:
827:
211:
31:
4635:
2996:
2294:(from which the advertised name "ReFuel" comes). RE85 is only suitable for
228:(iso-octane), is used as a reference standard to benchmark the tendency of
4430:
Republic Act No. 9367, "Biofuels Act of 2006", passed on January 12, 2007.
2244:
stations, and the "Petrobras Podium" (97 RON), sold at Petrobras stations.
3753:
2916:
Harwood, Richard; Coates, Christopher; Talbot, Christopher (2015-07-31).
2744:
2579:
the mountains, but at sea level the fuel may cause damage to the engine.
2556:
2185:
2095:
1943:
1752:
1484:
1292:
1275:
1204:
1154:
309:
A US gasoline station pump offering five different (R+M)/2 octane ratings
270:
229:
4113:
3788:
2743:
Octane became well known in American popular culture in the 1960s, when
2736:
A 1940s US propaganda poster using the term "octane" to emphasise power.
4412:"Leaded Gasoline Finally Phased Out", Philippine Star, January 1, 2001.
2655:
2594:
2306:
2152: in this section. Unsourced material may be challenged and removed.
1927:
1911:
1784:
1736:
1565:
1514:
1429:
1338:
1309:
1238:
1173:
1125:
787:
773:
729:
660:
604:
479: in this section. Unsourced material may be challenged and removed.
286:
247:
Octane ratings are not indicators of the energy content of fuels. (See
203:
3250:
4284:"VTT Technical Research Centre of Finland - Business from technology"
3929:"Why E10 petrol may not be driving your car, or your dollar, further"
2553:
2483:
2398:
2330:
Racing", a 100 RON fuel sold in selected stations. From August 2016,
1895:
1722:
1622:
1548:
1334:
1169:
948:
710:
641:
327:
221:
4606:
Beatty, Harold A. (2 March 1956). "Graham Edgar, Chemist of Parts".
3243:
Autoignition of n-butane/isobutane blends in a knock research engine
1341:, Great Britain, Slovenia and Spain, “Ampol Amplify 98 Unleaded” in
3952:
2757:
2629:
2563:
2541:
2410:
2111:
1606:
1499:
1446:
1425:
1401:
1397:
1393:
1234:
895:
438:
304:
262:
202:
3431:
3429:
3427:
1124:"Aral Super 95" in Germany, "Aral Super 95 E10" (10% ethanol) in
27:
Standard measure of the performance of an engine or aviation fuel
2968:
Steven A., Treese; Peter R., Pujado; David S. J., Jones (2015).
2598:
2222:
Brazilian National Agency of Petroleum, Natural Gas and Biofuels
2056:
Higher-octane, lower-energy-dense "thinner" fuels often contain
290:
282:
4561:
3536:"Automotive Gasoline: Products and Characteristics - Petrobras"
84:
mixture, which is ignited only near the end of the compression
4583:"Dictionary.com | Meanings & Definitions of English Words"
4333:"Not all fuels are the same, we dig deeper into shell v power"
4218:"BNamericas - EP Petroecuador comercializará en el mercado..."
3639:
MATCH Communications in Mathematical and in Computer Chemistry
2121:
1963:
1638:
550:
448:
3472:"FAQs – Questions, Answers, Gasoline Products – Petro-Canada"
3835:"Pelican's Perch #63:Where Should I Run My Engine? (Part 1)"
2353:
Italy: 95 RON is the only compulsory gasoline offered (
3658:
3656:
3654:
3652:
3412:. New Zealand: Nelson Petroleum Distributors. February 2021
2887:
Kemp, Kenneth W.; Brown, Theodore; Nelson, John D. (2003).
2549:
2406:
2226:
Agência Nacional do Petróleo, Gás Natural e Biocombustíveis
393:
See the table in the following section for a comparison.
4242:"الحكومة المصرية ترفع أسعار الوقود بنسبة تقترب من الضعف"
1375:
Pertamina "Pertamina Racing Fuel" (bioethanol blend) in
4134:
2533:
be anything above 98 RON with extra cleaning additives.
579:
318:
The most common type of octane rating worldwide is the
3795:
Verhelst, Sebastian; Wallner, Thomas (December 2009).
2719:
have an octane rating of -20 and 106.1, respectively (
2895:. Englewood Cliffs, N.J: Prentice Hall. p. 992.
1358:"Shell V-Power Nitro+ 99" "Tesco Momentum 99" In the
1072:"Mid-Grade Gasoline" in the United States and Canada
1032:, "Vivo Revvo 92" in Indonesia, "BP 92" in Indonesia
4047:"China V gasoline and diesel fuel quality standards"
3625:
3623:
3621:
3619:
3617:
3615:
2991:
2989:
2516:
Sweden: 95 RON, 98 RON and E85 are widely available.
326:). RON is determined by running the fuel in a test
30:"Hi-octane" redirects here. For the video game, see
4832:. Mechanical Engineering Series. pp. 199–226.
3696:
3694:
3262:
3260:
2090:In almost all general aviation piston engines, the
4517:"Vacationers, beware: Bad gas can damage your car"
2888:
2650:In 1927, Graham Edgar devised the method of using
1396:(Japanese Industrial Standards), "IP Plus 100" in
4867:Gasoline Refining and Testing, Table 3.1, page 32
4750:"What Does Octane Do In Gasoline? Octane Ratings"
4052:. International Council on Clean Transportation.
71:In contrast, fuels with lower octane (but higher
3595:"BP Ultimate 102 unleaded | BP Ultimate UK"
2946:. U.S. EPA, Region 10. June 1995. Archived from
2371:Lebanon: 95 RON and 98 RON are widely available.
4861:Research Octane Number by Hydrocarbon Structure
3630:Balaban, A. T.; Kier, L. B.; Joshi, N. (1992).
3095:"Standard Specification for Aviation Gasolines"
3042:The Arabian Journal for Science and Engineering
2368:Latvia: 95 RON and 98 RON are widely available.
1502:(northern Italy only, just a few gas stations)
183:commonly found in automobiles today, typically
3387:Shell phases out V-Power Racing fuel (100 RON)
3180:Johnson Operation and Maintenance Manual, 1999
2820:Ullmann's Encyclopedia of Industrial Chemistry
2066:hydrochloric acids that form due to that water
3797:"Hydrogen-fueled internal combustion engines"
3701:James J. Spivey; K. M. Dooley (August 2007).
3333:
3331:
3308:
3306:
3287:
3285:
2658:as reference chemicals, in order to rate the
2298:cars that can run on high-percentage ethanol.
1581:Gulf Endurance 102 Racing Fuel (sold only at
844:Pertamina "Pertalite" and Vivo "Revvo 90" in
8:
4491:"AAA Colorado ~ EnCompass Magazine - Online"
3754:"Biofuels - Types of Biofuels - Bioalcohols"
3707:. Royal Society of Chemistry. pp. 33–.
3530:
3528:
3526:
3524:
3522:
2972:(2 ed.). Springer. pp. 681, 1796.
2850:
2848:
2240:- 97 RON), the "OctaPro" (103 RON), sold at
3236:
3234:
2919:Chemistry for the IB Diploma Second Edition
1998:. Unsourced material may be challenged and
1408:- discontinued July 2008, "NPD 100Plus" in
217:(lower) is assigned the octane rating of 0.
3748:
3746:
2030:Higher octane ratings correlate to higher
609:
4000:
3998:
3996:
3801:Progress in Energy and Combustion Science
3589:
3587:
3191:"Product Specifications Plus 91(regular)"
2812:
2810:
2552:started a public trial of the super-high
2168:Learn how and when to remove this message
2018:Learn how and when to remove this message
1329:, "BP Ultimate 98/Mobil Synergy 8000" in
848:(will begin discontinuing sales in 2024)
539:Learn how and when to remove this message
2997:"Octane determination in Piston Engines"
2731:
2436:gasstations have 98 octane fuel as well.
1445:"Eni (or Agip) Blu Super +(or Tech)" in
1219:"Premium Gasoline" in the United States
582:by adding descriptive text and removing
157:) occurs when combustion of some of the
4347:"DOF - Diario Oficial de la Federación"
4016:from the original on 19 September 2011.
3729:"All DragRace Fuel Available at VPFuel"
2773:
2548:both offer 99 RON fuel. In April 2006,
4647:
4645:
4059:from the original on 27 September 2015
4029:"The problem with ethanol in gasoline"
401:Another type of octane rating, called
343:Another type of octane rating, called
2574:in higher-elevation areas, a typical
1673:"BP Ultimate 102" - now discontinued
437:The most common currently used fuel,
172:Knocking should not be confused with
7:
4830:Fundamentals of Combustion Processes
4702:"Chemical isomer - Energy Education"
3339:"Ecopetrol - Energía para el Futuro"
3314:"Ecopetrol - Energía para el Futuro"
3293:"Ecopetrol - Energía para el Futuro"
3268:"Ecopetrol - Energía para el Futuro"
3060:"Replacing Leaded Aviation Gasoline"
2150:adding citations to reliable sources
1996:adding citations to reliable sources
477:adding citations to reliable sources
385:Difference between RON, MON, and AKI
4266:"الحكومة المصرية ترفع أسعار الوقود"
4006:"MEDIDA PROVISÓRIA nº 532, de 2011"
3953:"Product Specification - Petroleum"
2855:Haitch, Richard (3 December 1978).
2626:Misconceptions around octane rating
4027:Russell, Richard (22 March 2016).
2857:"Who Helped Win Battle of Britain"
397:Observed Road Octane Number (RdON)
199:Iso-octane as a reference standard
25:
3407:"NPD 100Plus – 100 octane petrol"
373:), and often written on pumps as
360:Anti-Knock Index (AKI) or (R+M)/2
4536:"GoSunoco - Partner With Sunoco"
4254:from the original on 2014-12-01.
4145:from the original on 2014-02-18.
4123:from the original on 2014-02-22.
3764:from the original on 2014-04-16.
3739:from the original on 2020-03-30.
3324:from the original on 2012-06-19.
3278:from the original on 2012-06-19.
3029:from the original on 2011-07-27.
3007:from the original on 2013-10-29.
2970:Handbook of Petroleum Processing
2791:10.1016/B978-012663971-1.50011-7
2705:Octane Ratings of Octane Isomers
2606:U.S. State Fuel Octane Standards
2604:State standard gasoline grades:
2583:have almost completely replaced
2126:
1968:
1465:(RON and MON 100 by definition)
1241:, Pertamina "Pertamax Turbo" in
1149:, Pertamina "Pertamax Green" in
982:"Regular Gasoline/Petroleum" in
555:
453:
422:Aviation gasoline octane ratings
4879:Why are Octane levels important
4558:"E85 Refueling Location Search"
4395:from the original on 2017-04-07
4095:from the original on 2017-01-07
3927:Roberts, Natalie (2018-07-04).
3482:from the original on 2015-11-22
3369:from the original on 2022-01-12
3076:from the original on 2016-03-04
2482:Singapore: All four providers,
2212:(English: "Common Gasoline") -
2137:needs additional citations for
990:, Canada and the United States
464:needs additional citations for
377:. AKI is also sometimes called
236:fuels to resist self-ignition.
4682:www.mckinseyenergyinsights.com
4441:"Ceylon Petroleum Corporation"
3458:10.1016/j.apenergy.2012.02.073
3215:"Product Specifications Super"
2891:Chemistry: the central science
2566:fuel stations also supply the
1479:"Petron Blaze 100 Euro 4M" in
666:(RON and MON 0 by definition)
1:
4361:"100 Plus high octane petrol"
2829:10.1002/14356007.a16_719.pub3
2309:offer 100 RON gasoline (
1498:"San Marco Petroli F-101" in
1245:, Premium unleaded in the UK
900:Japanese Industrial Standards
45:, is a standard measure of a
4838:10.1007/978-1-4419-7943-8_10
4628:10.1126/science.123.3192.365
4515:Phelan, Mark (29 May 2013).
4385:"Tømmer tanken for 98 oktan"
1404:, "Shell V-Power Racing" in
1145:, "Total Performance 95" in
1028:, "Total Performance 92" in
314:Research Octane Number (RON)
248:
4801:"Definition of HIGH-OCTANE"
2570:produced 99 RON "Momentum".
403:Observed Road Octane Number
131:internal combustion engines
4946:
4775:Pure and Applied Chemistry
4179:"Din benzin hedder nu E10"
3821:10.1016/j.pecs.2009.08.001
3685:10.1016/j.fuel.2010.01.032
3156:Pure and Applied Chemistry
2675:Examples of misconceptions
2576:naturally aspirated engine
806:requirement for a typical
332:variable compression ratio
119:
55:internal combustion engine
29:
3957:Padma Oil Company Limited
1274:"Corriente (Regular)" in
1237:, "Aral SuperPlus 98" in
621:
618:
615:
612:
339:Motor Octane Number (MON)
185:electronic fuel injection
181:engine management systems
4730:Chemistry Stack Exchange
3874:"About United Petroleum"
3561:"Changes in Gasoline IV"
2560:BP Ultimate Unleaded 102
1291:"Extra (Super/Plus)" in
603:The RON/MON values of n-
49:'s ability to withstand
4805:www.merriam-webster.com
4787:10.1351/pac198855020199
4754:www.bellperformance.com
4193:"Gasoline requirements"
3977:"Petroleum Local Price"
3168:10.1351/pac198855020199
2823:. Weinheim: Wiley-VCH.
2709:Octane isomers such as
1153:, "Shell FuelSave " in
860:"Plus 91" (Regular) in
826:Pertamina "Premium" in
584:less pertinent examples
116:The problem: detonation
4873:Information in general
3903:Unitedpetroleum.com.au
3476:Retail.petro-canada.ca
2737:
2716:2,3,3-trimethylpentane
2635:
1769:2,2,3-trimethylpentane
1707:2,3,3-trimethylpentane
1392:"Premium" gasoline in
1203:"Shell V-Power 97" in
894:"Regular gasoline" in
381:(Pump Octane Number).
320:Research Octane Number
310:
226:2,2,4-Trimethylpentane
218:
208:2,2,4-Trimethylpentane
4523:. Detroit Free Press.
4079:"Manual de Productis"
2944:"Leaded Gas Phaseout"
2735:
2633:
2216:stations brand it as
2184:Australia: "regular"
1834:2,2,3-trimethylbutane
1564:Aral Ultimate 102 in
1400:, "Tamoil WR 100" in
877:"Súper" (Premium) in
308:
206:
99:The octane rating of
3130:"Petroleum and Coal"
3019:"Octane Explanation"
2922:. Hodder Education.
2785:. pp. 199–233.
2783:Fire Debris Analysis
2146:improve this article
1992:improve this section
1621:Petrobras Podium in
473:improve this article
4925:Petroleum economics
4620:1956Sci...123..365B
3837:. 13 December 2002.
3813:2009PECS...35..490V
3735:. 5 December 2019.
3677:2010Fuel...89.2713E
3450:2012ApEn...98...59D
2292:biodegradable waste
2118:Regional variations
2032:activation energies
1583:Silverstone Circuit
1424:"Shell V-Power" in
1141:"Shell V-Power" in
1103:"Super/Premium" in
580:improve the article
345:Motor Octane Number
301:Measurement methods
18:Motor octane number
4884:2018-06-14 at the
4706:energyeducation.ca
4161:crodux-derivati.hr
4033:The Globe and Mail
3501:"ExxonMobil Avgas"
3392:2011-02-22 at the
3001:vintagebonanza.com
2738:
2636:
2249:Atlantic Provinces
2234:Gasolina Aditivada
1059:2,3-dimethylbutane
1045:2,2-dimethylbutane
936:(dimethylpropane)
427:Aviation gasolines
330:at 600 rpm with a
311:
275:gasoline additives
253:Heat of combustion
219:
4900:HowStuffWorks.com
4847:978-1-4419-7942-1
4157:"Crodux derivati"
4135:"Lukoil Hrvatska"
3733:vpracingfuels.com
3714:978-0-85404-244-9
3671:(10): 2713–2720.
3219:www.recope.go.cr/
3195:www.recope.go.cr/
3102:Aviation-fuel.com
2979:978-3-319-14528-0
2800:978-0-12-663971-1
2728:Octane in Culture
2208:in Portuguese as
2178:
2177:
2170:
2028:
2027:
2020:
1957:
1956:
1849:VP C16 Race Fuel
1529:2,5-Dimethylfuran
1257:"YPF Infinia" in
1233:"IES 98 Plus" in
1024:"Shell Super" in
1007:"Pertamax 92" in
601:
600:
549:
548:
541:
523:
285:, iso-octane and
167:four-stroke cycle
101:aviation gasoline
16:(Redirected from
4937:
4896:How Octane Works
4851:
4816:
4815:
4813:
4812:
4797:
4791:
4790:
4770:
4764:
4763:
4761:
4760:
4746:
4740:
4739:
4737:
4736:
4722:
4716:
4715:
4713:
4712:
4698:
4692:
4691:
4689:
4688:
4674:
4668:
4667:
4665:
4664:
4649:
4640:
4639:
4603:
4597:
4596:
4594:
4593:
4579:
4573:
4572:
4570:
4569:
4560:. Archived from
4554:
4548:
4547:
4542:. Archived from
4531:
4525:
4524:
4512:
4506:
4505:
4503:
4502:
4493:. Archived from
4487:
4481:
4480:
4478:
4472:. Archived from
4467:
4459:
4453:
4452:
4447:. Archived from
4437:
4431:
4428:
4422:
4419:
4413:
4410:
4404:
4403:
4401:
4400:
4381:
4375:
4374:
4372:
4371:
4357:
4351:
4350:
4343:
4337:
4336:
4329:
4323:
4322:
4320:
4319:
4305:
4299:
4298:
4296:
4295:
4286:. Archived from
4280:
4274:
4273:
4262:
4256:
4255:
4238:
4232:
4231:
4229:
4228:
4214:
4208:
4207:
4205:
4204:
4189:
4183:
4182:
4175:
4169:
4168:
4163:. Archived from
4153:
4147:
4146:
4131:
4125:
4124:
4110:
4104:
4103:
4101:
4100:
4094:
4083:
4075:
4069:
4068:
4066:
4064:
4058:
4051:
4043:
4037:
4036:
4024:
4018:
4017:
4002:
3991:
3990:
3988:
3987:
3973:
3967:
3966:
3964:
3963:
3949:
3943:
3942:
3940:
3939:
3924:
3918:
3917:
3915:
3914:
3905:. Archived from
3895:
3889:
3888:
3886:
3885:
3876:. Archived from
3870:
3864:
3863:
3861:
3860:
3851:. Archived from
3845:
3839:
3838:
3831:
3825:
3824:
3792:
3777:SAE Transactions
3772:
3766:
3765:
3750:
3741:
3740:
3725:
3719:
3718:
3698:
3689:
3688:
3660:
3647:
3646:
3636:
3627:
3610:
3609:
3607:
3606:
3597:. Archived from
3591:
3582:
3581:
3579:
3578:
3572:
3566:. Archived from
3565:
3557:
3551:
3550:
3548:
3547:
3538:. Archived from
3532:
3517:
3516:
3514:
3513:
3497:
3491:
3490:
3488:
3487:
3468:
3462:
3461:
3433:
3422:
3421:
3419:
3417:
3411:
3403:
3397:
3384:
3378:
3377:
3375:
3374:
3368:
3361:
3353:
3347:
3346:
3343:ecopetrol.com.co
3335:
3326:
3325:
3318:ecopetrol.com.co
3310:
3301:
3300:
3297:ecopetrol.com.co
3289:
3280:
3279:
3272:ecopetrol.com.co
3264:
3255:
3254:
3238:
3229:
3228:
3226:
3225:
3211:
3205:
3204:
3202:
3201:
3187:
3181:
3178:
3172:
3171:
3151:
3145:
3144:
3142:
3141:
3132:. Archived from
3126:
3120:
3119:
3117:
3116:
3110:
3104:. Archived from
3099:
3091:
3085:
3084:
3082:
3081:
3075:
3064:
3056:
3050:
3049:
3037:
3031:
3030:
3015:
3009:
3008:
2993:
2984:
2983:
2965:
2959:
2958:
2956:
2955:
2940:
2934:
2933:
2913:
2907:
2906:
2894:
2884:
2878:
2877:
2871:
2869:
2852:
2843:
2842:
2814:
2805:
2804:
2778:
2660:knock resistance
2238:Gasolina Premium
2218:Gasolina Regular
2191:United Petroleum
2173:
2166:
2162:
2159:
2153:
2130:
2122:
2081:carburetor icing
2067:
2043:specific gravity
2023:
2016:
2012:
2009:
2003:
1972:
1964:
1817:isopropylbenzene
1337:, "Super 98" in
1172:, "Super 95" in
610:
596:
593:
587:
559:
558:
551:
544:
537:
533:
530:
524:
522:
481:
457:
449:
367:Anti-Knock Index
159:air/fuel mixture
75:) are ideal for
66:gasoline engines
57:without causing
21:
4945:
4944:
4940:
4939:
4938:
4936:
4935:
4934:
4915:Fuel technology
4905:
4904:
4886:Wayback Machine
4858:
4848:
4827:
4824:
4822:Further reading
4819:
4810:
4808:
4799:
4798:
4794:
4772:
4771:
4767:
4758:
4756:
4748:
4747:
4743:
4734:
4732:
4724:
4723:
4719:
4710:
4708:
4700:
4699:
4695:
4686:
4684:
4676:
4675:
4671:
4662:
4660:
4651:
4650:
4643:
4605:
4604:
4600:
4591:
4589:
4581:
4580:
4576:
4567:
4565:
4556:
4555:
4551:
4533:
4532:
4528:
4514:
4513:
4509:
4500:
4498:
4489:
4488:
4484:
4476:
4465:
4461:
4460:
4456:
4445:ceypetco.gov.lk
4439:
4438:
4434:
4429:
4425:
4420:
4416:
4411:
4407:
4398:
4396:
4383:
4382:
4378:
4369:
4367:
4359:
4358:
4354:
4345:
4344:
4340:
4331:
4330:
4326:
4317:
4315:
4307:
4306:
4302:
4293:
4291:
4282:
4281:
4277:
4270:Sky News Arabic
4264:
4263:
4259:
4250:. 5 July 2014.
4240:
4239:
4235:
4226:
4224:
4216:
4215:
4211:
4202:
4200:
4191:
4190:
4186:
4177:
4176:
4172:
4155:
4154:
4150:
4133:
4132:
4128:
4112:
4111:
4107:
4098:
4096:
4092:
4081:
4077:
4076:
4072:
4062:
4060:
4056:
4049:
4045:
4044:
4040:
4026:
4025:
4021:
4004:
4003:
3994:
3985:
3983:
3975:
3974:
3970:
3961:
3959:
3951:
3950:
3946:
3937:
3935:
3926:
3925:
3921:
3912:
3910:
3897:
3896:
3892:
3883:
3881:
3872:
3871:
3867:
3858:
3856:
3847:
3846:
3842:
3833:
3832:
3828:
3794:
3774:
3773:
3769:
3752:
3751:
3744:
3727:
3726:
3722:
3715:
3700:
3699:
3692:
3662:
3661:
3650:
3634:
3629:
3628:
3613:
3604:
3602:
3593:
3592:
3585:
3576:
3574:
3570:
3563:
3559:
3558:
3554:
3545:
3543:
3534:
3533:
3520:
3511:
3509:
3499:
3498:
3494:
3485:
3483:
3470:
3469:
3465:
3435:
3434:
3425:
3415:
3413:
3409:
3405:
3404:
3400:
3394:Wayback Machine
3385:
3381:
3372:
3370:
3366:
3359:
3355:
3354:
3350:
3337:
3336:
3329:
3312:
3311:
3304:
3291:
3290:
3283:
3266:
3265:
3258:
3240:
3239:
3232:
3223:
3221:
3213:
3212:
3208:
3199:
3197:
3189:
3188:
3184:
3179:
3175:
3153:
3152:
3148:
3139:
3137:
3128:
3127:
3123:
3114:
3112:
3108:
3097:
3093:
3092:
3088:
3079:
3077:
3073:
3062:
3058:
3057:
3053:
3039:
3038:
3034:
3017:
3016:
3012:
2995:
2994:
2987:
2980:
2967:
2966:
2962:
2953:
2951:
2942:
2941:
2937:
2930:
2915:
2914:
2910:
2903:
2886:
2885:
2881:
2867:
2865:
2854:
2853:
2846:
2839:
2816:
2815:
2808:
2801:
2780:
2779:
2775:
2771:
2754:
2748:English slang.
2730:
2707:
2699:
2696:
2688:
2685:
2677:
2645:engine knocking
2628:
2174:
2163:
2157:
2154:
2143:
2131:
2120:
2065:
2024:
2013:
2007:
2004:
1989:
1973:
1962:
1308:"SuperPlus" in
1086:"YPF Super" in
970:(methylbutane)
830:(discontinued)
695:2-methylheptane
622:AKI or (R+M)/2
597:
591:
588:
577:
560:
556:
545:
534:
528:
525:
488:"Octane rating"
482:
480:
470:
458:
447:
424:
415:
399:
387:
362:
353:ignition timing
341:
316:
303:
293:in the form of
201:
193:ignition timing
124:
122:Engine knocking
118:
113:
59:engine knocking
35:
28:
23:
22:
15:
12:
11:
5:
4943:
4941:
4933:
4932:
4927:
4922:
4917:
4907:
4906:
4903:
4902:
4893:
4888:
4875:
4874:
4870:
4869:
4863:
4862:
4857:
4856:External links
4854:
4853:
4852:
4846:
4823:
4820:
4818:
4817:
4792:
4781:(2): 199–206.
4765:
4741:
4717:
4693:
4669:
4641:
4598:
4587:Dictionary.com
4574:
4549:
4546:on 2007-04-30.
4526:
4507:
4482:
4479:on 2010-12-14.
4454:
4451:on 2014-05-31.
4432:
4423:
4414:
4405:
4391:. 2014-04-15.
4376:
4352:
4338:
4324:
4300:
4275:
4257:
4233:
4221:BNamericas.com
4209:
4184:
4170:
4167:on 2014-02-21.
4148:
4126:
4105:
4070:
4038:
4019:
3992:
3981:www.bpc.gov.bd
3968:
3944:
3919:
3890:
3865:
3840:
3826:
3807:(6): 490–527.
3767:
3758:biofuel.org.uk
3742:
3720:
3713:
3690:
3648:
3611:
3583:
3552:
3518:
3492:
3463:
3438:Applied Energy
3423:
3398:
3379:
3348:
3327:
3302:
3281:
3256:
3230:
3206:
3182:
3173:
3162:(2): 199–206.
3146:
3121:
3086:
3067:Txideafarm.com
3051:
3048:(2B): 179–186.
3032:
3010:
2985:
2978:
2960:
2935:
2928:
2908:
2901:
2879:
2862:New York Times
2844:
2838:978-3527306732
2837:
2806:
2799:
2772:
2770:
2767:
2766:
2765:
2760:
2753:
2750:
2729:
2726:
2706:
2703:
2697:
2695:
2692:
2686:
2684:
2681:
2676:
2673:
2627:
2624:
2623:
2622:
2618:
2614:
2610:
2609:
2608:
2581:Fuel injectors
2571:
2538:Super Unleaded
2534:
2530:
2526:
2523:
2520:
2517:
2514:
2512:
2508:
2505:
2502:
2499:
2480:
2468:
2460:
2457:
2453:
2444:
2440:
2437:
2433:
2429:
2425:
2421:
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2414:
2379:
2375:
2372:
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2366:
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2327:
2323:
2319:
2317:
2314:
2299:
2287:
2284:
2280:
2276:
2272:
2269:
2265:
2262:
2258:
2255:
2252:
2245:
2224:- Portuguese:
2210:Gasolina Comum
2205:
2202:
2198:
2195:
2176:
2175:
2134:
2132:
2125:
2119:
2116:
2026:
2025:
2008:September 2018
1976:
1974:
1967:
1961:
1958:
1955:
1954:
1952:
1949:
1946:
1940:
1939:
1936:
1933:
1930:
1924:
1923:
1920:
1917:
1914:
1908:
1907:
1904:
1901:
1898:
1892:
1891:
1888:
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1876:
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1860:
1859:
1856:
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1842:
1839:
1836:
1830:
1829:
1826:
1823:
1820:
1813:
1812:
1809:
1806:
1803:
1797:
1796:
1793:
1790:
1787:
1781:
1780:
1777:
1774:
1771:
1765:
1764:
1761:
1758:
1755:
1749:
1748:
1745:
1742:
1739:
1733:
1732:
1730:
1728:
1725:
1719:
1718:
1715:
1712:
1709:
1703:
1702:
1699:
1696:
1693:
1684:
1683:
1680:
1677:
1674:
1670:
1669:
1666:
1663:
1660:
1651:
1650:
1647:
1644:
1641:
1635:
1634:
1631:
1628:
1625:
1618:
1617:
1615:
1612:
1610:
1600:
1599:
1596:
1593:
1590:
1587:United Kingdom
1578:
1577:
1574:
1571:
1568:
1561:
1560:
1557:
1554:
1551:
1547:"Ultra 94" in
1541:
1540:
1537:
1534:
1531:
1525:
1524:
1522:
1520:
1517:
1511:
1510:
1508:
1506:
1503:
1495:
1494:
1492:
1490:
1487:
1476:
1475:
1472:
1469:
1466:
1459:
1458:
1455:
1452:
1449:
1442:
1441:
1438:
1435:
1432:
1421:
1420:
1418:
1415:
1412:
1389:
1388:
1385:
1382:
1379:
1372:
1371:
1368:
1365:
1362:
1360:United Kingdom
1355:
1354:
1351:
1348:
1345:
1322:
1321:
1318:
1315:
1312:
1305:
1304:
1301:
1298:
1295:
1288:
1287:
1284:
1281:
1278:
1271:
1270:
1267:
1264:
1261:
1254:
1253:
1251:
1249:
1246:
1230:
1229:
1226:
1223:
1220:
1216:
1215:
1213:
1211:
1208:
1200:
1199:
1196:
1193:
1190:
1186:
1185:
1182:
1179:
1176:
1165:
1164:
1162:
1160:
1157:
1138:
1137:
1134:
1131:
1128:
1121:
1120:
1117:
1114:
1111:
1100:
1099:
1096:
1093:
1090:
1083:
1082:
1079:
1076:
1073:
1069:
1068:
1066:
1063:
1061:
1055:
1054:
1052:
1049:
1047:
1041:
1040:
1038:
1036:
1033:
1021:
1020:
1017:
1014:
1011:
1001:
1000:
997:
994:
991:
979:
978:
976:
973:
971:
964:
963:
960:
957:
954:
945:
944:
942:
939:
937:
930:
929:
926:
923:
920:
911:
910:
908:
906:
903:
891:
890:
887:
884:
881:
874:
873:
870:
867:
864:
857:
856:
854:
852:
849:
841:
840:
837:
834:
831:
823:
822:
819:
816:
813:
811:outboard motor
803:
802:
799:
796:
793:
784:
783:
781:
779:
776:
770:
769:
767:
764:
762:
760:3-methylhexane
756:
755:
752:
749:
746:
744:2-methylhexane
740:
739:
737:
735:
732:
726:
725:
722:
719:
716:
707:
706:
703:
700:
697:
691:
690:
688:
686:
683:
677:
676:
673:
670:
667:
657:
656:
653:
650:
647:
638:
637:
635:
633:
630:
624:
623:
620:
617:
614:
599:
598:
563:
561:
554:
547:
546:
461:
459:
452:
446:
443:
423:
420:
414:
411:
398:
395:
386:
383:
361:
358:
340:
337:
315:
312:
302:
299:
295:tetraethyllead
241:normal heptane
200:
197:
187:(EFI), have a
128:spark ignition
120:Main article:
117:
114:
112:
109:
77:diesel engines
73:cetane numbers
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
4942:
4931:
4928:
4926:
4923:
4921:
4918:
4916:
4913:
4912:
4910:
4901:
4897:
4894:
4892:
4889:
4887:
4883:
4880:
4877:
4876:
4872:
4871:
4868:
4865:
4864:
4860:
4859:
4855:
4849:
4843:
4839:
4835:
4831:
4826:
4825:
4821:
4806:
4802:
4796:
4793:
4788:
4784:
4780:
4776:
4769:
4766:
4755:
4751:
4745:
4742:
4731:
4727:
4721:
4718:
4707:
4703:
4697:
4694:
4683:
4679:
4673:
4670:
4658:
4654:
4648:
4646:
4642:
4637:
4633:
4629:
4625:
4621:
4617:
4614:(3192): 365.
4613:
4609:
4602:
4599:
4588:
4584:
4578:
4575:
4564:on 2008-12-07
4563:
4559:
4553:
4550:
4545:
4541:
4540:sunocoinc.com
4537:
4534:Sunoco, Inc.
4530:
4527:
4522:
4518:
4511:
4508:
4497:on 2014-01-10
4496:
4492:
4486:
4483:
4475:
4471:
4464:
4458:
4455:
4450:
4446:
4442:
4436:
4433:
4427:
4424:
4418:
4415:
4409:
4406:
4394:
4390:
4389:Altaposten.no
4386:
4380:
4377:
4366:
4362:
4356:
4353:
4348:
4342:
4339:
4334:
4328:
4325:
4314:
4310:
4304:
4301:
4290:on 2012-03-08
4289:
4285:
4279:
4276:
4271:
4267:
4261:
4258:
4253:
4249:
4248:
4243:
4237:
4234:
4222:
4219:
4213:
4210:
4199:on 2016-03-04
4198:
4194:
4188:
4185:
4180:
4174:
4171:
4166:
4162:
4158:
4152:
4149:
4144:
4140:
4136:
4130:
4127:
4122:
4118:
4115:
4109:
4106:
4091:
4087:
4080:
4074:
4071:
4055:
4048:
4042:
4039:
4034:
4030:
4023:
4020:
4015:
4011:
4010:senado.gov.br
4007:
4001:
3999:
3997:
3993:
3982:
3978:
3972:
3969:
3958:
3954:
3948:
3945:
3934:
3930:
3923:
3920:
3909:on 2016-12-23
3908:
3904:
3900:
3894:
3891:
3880:on 2010-09-02
3879:
3875:
3869:
3866:
3855:on 2010-08-30
3854:
3850:
3849:"Premium 100"
3844:
3841:
3836:
3830:
3827:
3822:
3818:
3814:
3810:
3806:
3802:
3798:
3790:
3786:
3782:
3778:
3771:
3768:
3763:
3759:
3755:
3749:
3747:
3743:
3738:
3734:
3730:
3724:
3721:
3716:
3710:
3706:
3705:
3697:
3695:
3691:
3686:
3682:
3678:
3674:
3670:
3666:
3659:
3657:
3655:
3653:
3649:
3644:
3640:
3633:
3626:
3624:
3622:
3620:
3618:
3616:
3612:
3601:on 2010-07-24
3600:
3596:
3590:
3588:
3584:
3573:on 2012-08-02
3569:
3562:
3556:
3553:
3542:on 2018-06-20
3541:
3537:
3531:
3529:
3527:
3525:
3523:
3519:
3508:
3507:
3502:
3496:
3493:
3481:
3477:
3473:
3467:
3464:
3459:
3455:
3451:
3447:
3443:
3439:
3432:
3430:
3428:
3424:
3408:
3402:
3399:
3395:
3391:
3388:
3383:
3380:
3365:
3358:
3357:"IP Plus 100"
3352:
3349:
3344:
3340:
3334:
3332:
3328:
3323:
3319:
3315:
3309:
3307:
3303:
3298:
3294:
3288:
3286:
3282:
3277:
3273:
3269:
3263:
3261:
3257:
3252:
3248:
3244:
3237:
3235:
3231:
3220:
3216:
3210:
3207:
3196:
3192:
3186:
3183:
3177:
3174:
3169:
3165:
3161:
3157:
3150:
3147:
3136:on 2009-04-25
3135:
3131:
3125:
3122:
3111:on 2016-04-15
3107:
3103:
3096:
3090:
3087:
3072:
3068:
3061:
3055:
3052:
3047:
3043:
3036:
3033:
3028:
3024:
3020:
3014:
3011:
3006:
3002:
2998:
2992:
2990:
2986:
2981:
2975:
2971:
2964:
2961:
2950:on 2008-06-03
2949:
2945:
2939:
2936:
2931:
2929:9781471829222
2925:
2921:
2920:
2912:
2909:
2904:
2902:0-13-066997-0
2898:
2893:
2892:
2883:
2880:
2876:
2864:
2863:
2858:
2851:
2849:
2845:
2840:
2834:
2830:
2826:
2822:
2821:
2813:
2811:
2807:
2802:
2796:
2792:
2788:
2784:
2777:
2774:
2768:
2764:
2763:Cetane number
2761:
2759:
2756:
2755:
2751:
2749:
2746:
2741:
2734:
2727:
2725:
2722:
2718:
2717:
2712:
2704:
2702:
2693:
2691:
2682:
2680:
2674:
2672:
2669:
2665:
2661:
2657:
2653:
2648:
2646:
2642:
2632:
2625:
2619:
2615:
2611:
2607:
2603:
2602:
2600:
2596:
2591:
2586:
2582:
2577:
2572:
2569:
2565:
2561:
2558:
2555:
2551:
2547:
2543:
2539:
2535:
2531:
2527:
2524:
2521:
2518:
2515:
2513:
2509:
2506:
2503:
2500:
2497:
2493:
2489:
2485:
2481:
2477:
2473:
2469:
2465:
2461:
2458:
2454:
2450:
2445:
2441:
2438:
2434:
2430:
2426:
2422:
2419:
2415:
2412:
2408:
2404:
2400:
2396:
2392:
2388:
2384:
2380:
2376:
2373:
2370:
2367:
2363:
2359:
2356:
2352:
2349:
2345:
2341:
2337:
2333:
2328:
2324:
2320:
2318:
2315:
2312:
2311:Shell V-Power
2308:
2304:
2300:
2297:
2293:
2288:
2285:
2281:
2277:
2273:
2270:
2266:
2263:
2259:
2256:
2253:
2250:
2246:
2243:
2239:
2235:
2231:
2227:
2223:
2219:
2215:
2211:
2206:
2203:
2199:
2196:
2192:
2187:
2183:
2182:
2181:
2172:
2169:
2161:
2151:
2147:
2141:
2140:
2135:This section
2133:
2129:
2124:
2123:
2117:
2115:
2113:
2109:
2105:
2101:
2097:
2093:
2088:
2084:
2082:
2078:
2074:
2073:ideal gas law
2069:
2063:
2059:
2054:
2052:
2051:specific heat
2048:
2044:
2039:
2035:
2033:
2022:
2019:
2011:
2001:
1997:
1993:
1987:
1986:
1982:
1977:This section
1975:
1971:
1966:
1965:
1959:
1953:
1950:
1947:
1945:
1942:
1941:
1937:
1934:
1931:
1929:
1926:
1925:
1921:
1918:
1915:
1913:
1910:
1909:
1905:
1902:
1899:
1897:
1894:
1893:
1889:
1886:
1883:
1881:
1878:
1877:
1873:
1870:
1867:
1865:
1862:
1861:
1857:
1854:
1851:
1848:
1847:
1843:
1840:
1837:
1835:
1832:
1831:
1827:
1824:
1821:
1818:
1815:
1814:
1810:
1807:
1804:
1802:
1799:
1798:
1794:
1791:
1788:
1786:
1783:
1782:
1778:
1775:
1772:
1770:
1767:
1766:
1762:
1759:
1756:
1754:
1751:
1750:
1746:
1743:
1740:
1738:
1735:
1734:
1731:
1729:
1726:
1724:
1721:
1720:
1716:
1713:
1710:
1708:
1705:
1704:
1700:
1697:
1694:
1692:
1690:
1686:
1685:
1681:
1678:
1675:
1672:
1671:
1667:
1664:
1661:
1659:
1657:
1653:
1652:
1648:
1645:
1642:
1640:
1637:
1636:
1632:
1629:
1626:
1624:
1620:
1619:
1616:
1613:
1611:
1608:
1605:
1602:
1601:
1597:
1594:
1591:
1588:
1584:
1580:
1579:
1575:
1572:
1569:
1567:
1563:
1562:
1558:
1555:
1552:
1550:
1546:
1543:
1542:
1538:
1535:
1532:
1530:
1527:
1526:
1523:
1521:
1518:
1516:
1513:
1512:
1509:
1507:
1504:
1501:
1497:
1496:
1493:
1491:
1488:
1486:
1482:
1478:
1477:
1473:
1470:
1467:
1464:
1461:
1460:
1456:
1453:
1450:
1448:
1444:
1443:
1439:
1436:
1433:
1431:
1427:
1423:
1422:
1419:
1416:
1413:
1411:
1407:
1403:
1399:
1395:
1391:
1390:
1386:
1383:
1380:
1378:
1374:
1373:
1369:
1366:
1363:
1361:
1357:
1356:
1352:
1349:
1346:
1344:
1340:
1336:
1332:
1328:
1324:
1323:
1319:
1316:
1313:
1311:
1307:
1306:
1302:
1299:
1296:
1294:
1290:
1289:
1285:
1282:
1279:
1277:
1273:
1272:
1268:
1265:
1262:
1260:
1256:
1255:
1252:
1250:
1247:
1244:
1240:
1236:
1232:
1231:
1227:
1224:
1221:
1218:
1217:
1214:
1212:
1209:
1206:
1202:
1201:
1197:
1194:
1191:
1188:
1187:
1183:
1180:
1177:
1175:
1171:
1167:
1166:
1163:
1161:
1158:
1156:
1152:
1148:
1144:
1140:
1139:
1135:
1132:
1129:
1127:
1123:
1122:
1118:
1115:
1112:
1110:
1106:
1102:
1101:
1097:
1094:
1091:
1089:
1085:
1084:
1080:
1077:
1074:
1071:
1070:
1067:
1064:
1062:
1060:
1057:
1056:
1053:
1050:
1048:
1046:
1043:
1042:
1039:
1037:
1034:
1031:
1027:
1023:
1022:
1018:
1015:
1012:
1010:
1006:
1003:
1002:
998:
995:
992:
989:
985:
981:
980:
977:
974:
972:
969:
966:
965:
961:
958:
955:
953:
951:
947:
946:
943:
940:
938:
935:
932:
931:
927:
924:
921:
919:
917:
913:
912:
909:
907:
904:
901:
897:
893:
892:
888:
885:
882:
880:
876:
875:
871:
868:
865:
863:
859:
858:
855:
853:
850:
847:
843:
842:
838:
835:
832:
829:
825:
824:
820:
817:
814:
812:
809:
805:
804:
800:
797:
794:
792:
790:
786:
785:
782:
780:
777:
775:
772:
771:
768:
765:
763:
761:
758:
757:
753:
750:
747:
745:
742:
741:
738:
736:
733:
731:
728:
727:
723:
720:
717:
715:
713:
709:
708:
704:
701:
698:
696:
693:
692:
689:
687:
684:
682:
679:
678:
674:
671:
668:
665:
663:
659:
658:
654:
651:
648:
646:
644:
640:
639:
636:
634:
631:
629:
626:
625:
611:
608:
606:
595:
585:
581:
575:
573:
569:
564:This section
562:
553:
552:
543:
540:
532:
521:
518:
514:
511:
507:
504:
500:
497:
493:
490: –
489:
485:
484:Find sources:
478:
474:
468:
467:
462:This section
460:
456:
451:
450:
444:
442:
440:
435:
433:
428:
421:
419:
412:
410:
408:
404:
396:
394:
391:
384:
382:
380:
376:
372:
368:
359:
357:
354:
350:
346:
338:
336:
333:
329:
325:
321:
313:
307:
300:
298:
296:
292:
288:
284:
280:
276:
272:
268:
267:alcohol fuels
264:
259:
256:
254:
250:
245:
242:
237:
235:
231:
227:
223:
216:
214:
209:
205:
198:
196:
194:
190:
186:
182:
177:
175:
170:
168:
164:
160:
156:
152:
148:
144:
140:
136:
132:
129:
123:
115:
110:
108:
106:
102:
97:
95:
91:
87:
83:
78:
74:
69:
67:
62:
60:
56:
52:
48:
44:
43:octane number
40:
39:octane rating
33:
19:
4920:Oil refining
4891:Gasoline FAQ
4829:
4809:. Retrieved
4807:. 2024-04-13
4804:
4795:
4778:
4774:
4768:
4757:. Retrieved
4753:
4744:
4733:. Retrieved
4729:
4720:
4709:. Retrieved
4705:
4696:
4685:. Retrieved
4681:
4672:
4661:. Retrieved
4657:www.eesi.org
4656:
4611:
4607:
4601:
4590:. Retrieved
4586:
4577:
4566:. Retrieved
4562:the original
4552:
4544:the original
4539:
4529:
4520:
4510:
4499:. Retrieved
4495:the original
4485:
4474:the original
4469:
4457:
4449:the original
4444:
4435:
4426:
4417:
4408:
4397:. Retrieved
4388:
4379:
4368:. Retrieved
4364:
4355:
4341:
4327:
4316:. Retrieved
4312:
4303:
4292:. Retrieved
4288:the original
4278:
4269:
4260:
4245:
4236:
4225:. Retrieved
4223:(in Spanish)
4220:
4212:
4201:. Retrieved
4197:the original
4187:
4173:
4165:the original
4160:
4151:
4138:
4129:
4116:
4108:
4097:. Retrieved
4086:Recope.go.cr
4085:
4073:
4061:. Retrieved
4041:
4032:
4022:
4009:
3984:. Retrieved
3980:
3971:
3960:. Retrieved
3956:
3947:
3936:. Retrieved
3932:
3922:
3911:. Retrieved
3907:the original
3902:
3899:"Ethanol 85"
3893:
3882:. Retrieved
3878:the original
3868:
3857:. Retrieved
3853:the original
3843:
3829:
3804:
3800:
3780:
3776:
3770:
3757:
3732:
3723:
3703:
3668:
3664:
3642:
3638:
3603:. Retrieved
3599:the original
3575:. Retrieved
3568:the original
3555:
3544:. Retrieved
3540:the original
3510:. Retrieved
3504:
3495:
3484:. Retrieved
3475:
3466:
3441:
3437:
3414:. Retrieved
3401:
3382:
3371:. Retrieved
3351:
3342:
3317:
3296:
3271:
3242:
3222:. Retrieved
3218:
3209:
3198:. Retrieved
3194:
3185:
3176:
3159:
3155:
3149:
3138:. Retrieved
3134:the original
3124:
3113:. Retrieved
3106:the original
3101:
3089:
3078:. Retrieved
3066:
3054:
3045:
3041:
3035:
3022:
3013:
3000:
2969:
2963:
2952:. Retrieved
2948:the original
2938:
2918:
2911:
2890:
2882:
2873:
2866:. Retrieved
2860:
2818:
2782:
2776:
2742:
2739:
2720:
2714:
2710:
2708:
2700:
2689:
2678:
2667:
2663:
2659:
2649:
2637:
2590:turbocharged
2585:carburettors
2559:
2537:
2424:Petrotrans).
2354:
2237:
2233:
2229:
2225:
2217:
2209:
2179:
2164:
2155:
2144:Please help
2139:verification
2136:
2104:pre-ignition
2092:fuel mixture
2089:
2085:
2070:
2055:
2040:
2036:
2029:
2014:
2005:
1990:Please help
1978:
1801:ethylbenzene
1688:
1655:
1639:E85 gasoline
1545:Petro-Canada
1333:, "SP98" in
949:
915:
788:
711:
661:
642:
602:
589:
578:Please help
566:may contain
565:
535:
526:
516:
509:
502:
495:
483:
471:Please help
466:verification
463:
436:
432:supercharger
425:
416:
413:Octane Index
406:
402:
400:
392:
388:
378:
374:
370:
366:
363:
348:
344:
342:
323:
319:
317:
260:
257:
246:
238:
220:
212:
189:knock sensor
178:
174:pre-ignition
171:
154:
150:
146:
142:
138:
134:
125:
105:World War II
98:
94:pre-ignition
88:by electric
82:air and fuel
70:
63:
42:
38:
36:
3783:: 264–274.
3023:runyard.org
2694:Statement 2
2683:Statement 1
2462:Russia and
2391:Guadalajara
2077:undersquare
2062:hygroscopic
1880:propan-1-ol
1864:propan-2-ol
1614:99.6 (min)
1481:Philippines
1410:New Zealand
1331:New Zealand
1105:New Zealand
988:New Zealand
681:diesel fuel
147:spark knock
90:spark plugs
51:compression
4909:Categories
4811:2024-04-15
4759:2024-04-04
4735:2024-04-15
4711:2024-04-03
4687:2024-04-03
4663:2024-04-03
4592:2024-04-03
4568:2008-10-22
4501:2013-06-04
4399:2017-01-06
4370:2018-01-14
4318:2018-04-12
4313:CarAndBike
4294:2012-04-13
4247:BBC Arabic
4227:2023-07-19
4203:2012-06-21
4114:"INA d.d."
4099:2017-01-06
4063:7 February
3986:2018-03-06
3962:2018-03-06
3938:2019-07-26
3913:2017-01-06
3884:2010-09-01
3859:2010-09-01
3605:2010-12-21
3577:2011-08-27
3546:2018-06-19
3512:2023-03-04
3506:ExxonMobil
3486:2017-01-06
3373:2022-01-12
3224:2021-11-09
3200:2021-11-09
3140:2009-03-28
3115:2017-01-06
3080:2017-01-06
2954:2012-06-15
2769:References
2664:iso-octane
2652:iso-octane
2488:ExxonMobil
2413:and Akron.
2228:or simply
2100:detonation
2083:to occur.
1604:ExxonMobil
1463:iso-octane
1207:and Chile
968:Isopentane
934:Neopentane
879:Costa Rica
862:Costa Rica
808:two-stroke
628:hexadecane
572:irrelevant
499:newspapers
265:, LPG and
251:below and
163:spark plug
143:detonation
111:Principles
4521:USA TODAY
4365:npd.co.nz
4139:lukoil.hr
3793:cited by
3704:Catalysis
3444:: 59–68.
2668:n-heptane
2656:n-heptane
2568:Greenergy
2472:Fuel dyes
2467:unleaded.
2417:stations.
2395:Querétaro
2387:Monterrey
2361:unleaded.
2332:Pertamina
2296:flexifuel
2279:unleaded.
2214:Petrobras
2158:June 2024
1979:does not
1948:> 130
1819:(cumene)
1406:Australia
1377:Indonesia
1343:Australia
1327:Singapore
1259:Argentina
1243:Indonesia
1151:Indonesia
1147:Indonesia
1143:Indonesia
1109:Australia
1088:Argentina
1030:Indonesia
1026:Indonesia
1009:Indonesia
1005:Pertamina
984:Australia
846:Indonesia
828:Indonesia
774:1-heptene
730:1-pentene
632:< −30
592:June 2023
568:excessive
529:June 2023
32:Hi-Octane
4882:Archived
4678:"Octane"
4636:17736435
4393:Archived
4252:Archived
4143:Archived
4121:Archived
4090:Archived
4088:. 2011.
4054:Archived
4014:Archived
3933:ABC News
3789:44687302
3762:Archived
3737:Archived
3645:: 13–27.
3480:Archived
3416:6 August
3390:Archived
3364:Archived
3322:Archived
3276:Archived
3071:Archived
3027:Archived
3005:Archived
2752:See also
2745:gasoline
2711:n-octane
2641:cylinder
2557:gasoline
2378:outlets.
2242:Ipiranga
2186:unleaded
2096:throttle
1944:hydrogen
1753:methanol
1691:-butanol
1643:102-105
1485:Malaysia
1293:Colombia
1276:Colombia
1205:Malaysia
1155:Malaysia
918:-butanol
791:-pentane
664:-heptane
574:examples
445:Examples
277:include
271:methanol
269:such as
230:gasoline
215:-heptane
135:knocking
4616:Bibcode
4608:Science
3809:Bibcode
3673:Bibcode
3446:Bibcode
3251:5509255
2868:29 July
2597:-based
2595:ethanol
2322:forces.
2102:and/or
2058:alcohol
2000:removed
1985:sources
1960:Effects
1928:toluene
1912:methane
1785:propane
1737:ethanol
1658:-butane
1585:in the
1566:Germany
1515:benzene
1430:Germany
1339:Belgium
1310:Germany
1239:Germany
1174:Belgium
1126:Germany
952:-butane
714:-hexane
645:-octane
605:heptane
513:scholar
375:(R+M)/2
287:toluene
249:Effects
222:Octanes
155:pinking
151:pinging
4930:Scales
4844:
4659:. EESI
4634:
4470:bp.com
4117:ina.hr
3787:
3711:
3249:
2976:
2926:
2899:
2875:given.
2835:
2797:
2554:octane
2484:Caltex
2449:Petron
2399:Puebla
2383:Valero
2365:"F-1".
2261:extra)
1906:116.5
1896:xylene
1858:117.5
1841:101.3
1838:112.1
1773:109.6
1763:98.65
1757:108.7
1747:99.15
1741:108.6
1723:ethane
1711:106.1
1682:97–98
1679:93–94
1649:94–96
1646:85-87
1623:Brazil
1609:100LL
1598:97–98
1595:93–94
1553:101.5
1549:Canada
1533:101.3
1353:93–94
1350:89–90
1335:France
1228:91–93
1225:86–88
1222:96–98
1198:92–93
1195:87–88
1184:90–91
1181:85–86
1170:France
1081:89–90
1078:84–85
1075:94–95
996:82–83
993:91–92
685:15–25
655:−18.5
515:
508:
501:
494:
486:
328:engine
137:(also
86:stroke
53:in an
4477:(PDF)
4466:(PDF)
4093:(PDF)
4082:(PDF)
4057:(PDF)
4050:(PDF)
3785:JSTOR
3635:(PDF)
3571:(PDF)
3564:(PDF)
3410:(PDF)
3396:– MRT
3367:(PDF)
3360:(PDF)
3109:(PDF)
3098:(PDF)
3074:(PDF)
3063:(PDF)
2758:Avgas
2564:Tesco
2546:Shell
2542:Tesco
2496:Shell
2443:2016.
2411:Mobil
2403:Shell
2355:verde
2340:Shell
2336:Total
2303:Shell
2112:avgas
2047:power
1776:99.9
1760:88.6
1744:89.7
1714:99.4
1665:97.6
1607:Avgas
1539:94.7
1536:88.1
1500:Italy
1447:Italy
1426:Italy
1402:Italy
1398:Italy
1394:Japan
1280:91.5
1235:Italy
1065:94.4
1051:93.4
975:90.3
959:90.1
941:80.2
896:Japan
798:61.9
766:55.0
754:45.2
751:46.4
721:26.0
702:23.8
613:Fuel
520:JSTOR
506:books
439:100LL
263:avgas
179:Most
153:, or
139:knock
41:, or
4842:ISBN
4632:PMID
4463:"BP"
4065:2016
3709:ISBN
3665:Fuel
3418:2023
3247:OSTI
2974:ISBN
2924:ISBN
2897:ISBN
2870:2021
2833:ISBN
2795:ISBN
2713:and
2666:and
2654:and
2599:E-85
2544:and
2529:95+.
2494:and
2456:100.
2397:and
2338:and
2307:Aral
1983:any
1981:cite
1938:114
1935:107
1932:121
1922:120
1919:120
1916:120
1903:115
1900:118
1890:108
1884:118
1874:108
1868:118
1855:118
1852:117
1844:106
1828:107
1825:102
1822:112
1811:106
1805:112
1795:105
1789:112
1779:105
1727:108
1717:103
1695:103
1676:102
1668:100
1662:102
1627:102
1592:102
1570:102
1519:101
1505:101
1489:100
1483:and
1474:100
1471:100
1468:100
1451:100
1434:100
1428:and
1414:100
1381:100
1107:and
652:−17
649:−20
619:MON
616:RON
492:news
407:RdON
291:Lead
283:ETBE
279:MTBE
47:fuel
4898:at
4834:doi
4783:doi
4624:doi
4612:123
3817:doi
3781:115
3681:doi
3454:doi
3164:doi
2825:doi
2787:doi
2721:RON
2492:SPC
2464:CIS
2305:or
2268:98.
2230:ANP
2148:by
2108:EGT
1994:by
1951:60
1887:98
1871:98
1808:99
1792:97
1701:97
1698:91
1633:97
1630:88
1576:95
1573:88
1559:94
1556:88
1457:94
1454:87
1440:94
1437:88
1417:89
1387:93
1384:86
1370:93
1367:87
1364:99
1347:98
1320:93
1317:88
1314:98
1303:87
1300:79
1297:95
1286:81
1283:70
1269:93
1266:87
1263:98
1248:98
1210:97
1192:97
1178:95
1159:95
1136:90
1133:85
1130:95
1119:90
1116:85
1113:95
1098:90
1095:84
1092:95
1035:92
1019:87
1016:82
1013:92
999:87
962:92
956:94
928:83
925:71
922:92
905:90
889:89
886:83
883:95
872:85
869:79
866:91
851:90
839:83
836:78
833:88
821:67
801:62
795:62
778:60
748:44
734:34
724:26
718:25
705:23
699:23
570:or
475:by
379:PON
371:AKI
349:MON
324:RON
234:LPG
232:or
126:In
37:An
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4779:55
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